Effects of topping and non-topping on growth-regulating hormones of flue-cured tobacco (Nicotiana tabacum L.)-a proteomic analysis

Kaiyuan Gu; Li-E Yang; Ke Ren; Xianxue Luo; Xiao Qin; Michiel Op de Beeck; Conglian He; Li Jian; Yi Chen

doi:10.3389/fpls.2023.1255252

Effects of topping and non-topping on growth-regulating hormones of flue-cured tobacco (Nicotiana tabacum L.)-a proteomic analysis

Front Plant Sci. 2023 Oct 30:14:1255252. doi: 10.3389/fpls.2023.1255252. eCollection 2023.

Authors

Kaiyuan Gu^#¹, Li-E Yang^#², Ke Ren¹, Xianxue Luo³, Xiao Qin³, Michiel Op de Beeck⁴, Conglian He¹, Li Jian⁵, Yi Chen¹

Affiliations

¹ Agronomic Center, Yunnan Academy of Tobacco Agricultural Sciences, Kunming, Yunnan, China.
² Biotechnology and Germplasm Resources Institute, Yunnan Academy of Agricultural Sciences, Kunming, Yunnan, China.
³ Raw material center, Hunan Zhangjiajie Municipal Tobacco Co., Zhangjiajie, Hunan, China.
⁴ Centre for Environmental and Climate Research, Lund University, Lund, Sweden.
⁵ Key Laboratory of Urban Environment and Health, Instituteo of Urban Enviroment, Chinense Academy of Sciences, Xiamen, Fujian, China.

^# Contributed equally.

Abstract

Introduction: Until now, the mechanism underlying the impact of topping on hormone regulation in tobacco plants remains unclear, and most studies investigating the hormone signaling pathways in plants rely on genes or transcriptional pathways.

Methods: This study examines the regulatory mechanisms of hormones in the roots and leaves of tobacco plants with and without topping at the protein level.

Results: The results demonstrate that, compared with non-topped plants, topping leads to a decrease in the levels of IAA (auxin), ABA (abscisic acid), and GA (gibberellin) hormones in the leaves, whereas the content of the JA (jasmonic acid) hormone increases. Furthermore, in the roots, topping results in an increase in the levels of IAA, ABA, and JA hormones, along with a decrease in GA content. In the leaves, a total of 258 significantly different proteins were identified before and after topping, with 128 proteins upregulated and 130 proteins downregulated. In the roots, there were 439 proteins with significantly different quantities before and after topping, consisting of 211 upregulated proteins and 228 downregulated proteins. Notably, these proteins were closely associated with the metabolic and biosynthetic pathways of secondary metabolites, as indicated by functional categorization.

Conclusions: When integrating the hormone changes and the proteomics results, it is evident that topping leads to increased metabolic activity and enhanced hormone synthesis in the root system. This research provides a theoretical foundation for further investigations into the regulation and signaling mechanisms of hormones at the protein level before and after topping in plants.

Keywords: leaves and roots; plant hormones; proteomics; tobacco; topping.

Grants and funding

This work was supported by the Science and Technology Project of China National Tobacco Corporation (Grant No. 110202102007), the Yunnan Applied Fundamental Research Projects (202305AD160036), and the Yunnan Academy of Tobacco Agricultural Sciences (Grant Nos. 2021530000241035; 2023530401641007). The funders were not involved in the study design, collection, analysis, interpretation of data, the writing of this article, or the decision to submit it for publication.